Abstract
This paper addresses two questions: 1) What is the relation of hemoglobin in the second gestational month to preterm birth and low birth weight? 2) How does the relation differ when hemoglobin in the fifth or eighth month or the lowest pregnancy hemoglobin are examined in place of first trimester values? These relations were examined prospectively in 829 women from Shanghai, China in 1991-1992. The population was nearly homogeneous by race, parity, antenatal care, and smoking. Rates of birth Outcomes were con, pared between hemoglobin categories based on 10 g/liter groupings, with 110-119 g/liter as the reference group. Rates of low birth weight and preterm birth (but not small-for-gestational age) were related to early pregnancy hemoglobin concentration in a U-shaped manner. The relative risks (95% confidence intervals) for preterm birth in women by g/liter of hemoglobin were 2.52 (0.95-6.64) for ≥130 g/liter, 1.11 (0.41-2.99) for 120- 129 g/liter, 1.64 (0.77-3.47) for 100-109 g/liter, 2.63 (1.17-5.90) for 90- 99 g/liter, and 3.73 (1.36-10.23) for 60-89 g/liter. Use of hemoglobin values in the fifth or eighth month attenuated the association with preterm birth. When lowest pregnancy hemoglobin values were used, the association of anemia with both outcomes was obscured, and risk of preterm birth at high hemoglobin values increased dramatically.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 998-1006 |
| Number of pages | 9 |
| Journal | American Journal of Epidemiology |
| Volume | 148 |
| Issue number | 10 |
| State | Published - Nov 15 1998 |
| Externally published | Yes |
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Keywords
- Anemia
- Hemoglobins
- Infant, low birth weight
- Infant, premature
- Infant, small for gestational age
- Pregnancy
ASJC Scopus subject areas
- Epidemiology
Cite this
Relation of hemoglobin measured at different times in pregnancy to preterm birth and low birth weight in Shanghai, China. / Zhou, Li Ming; Yang, Wen Wei; Hua, Jia Zeng; Deng, Chun Qin; Tao, Xu Guang; Stoltzfus, Rebecca J.
In: American Journal of Epidemiology, Vol. 148, No. 10, 15.11.1998, p. 998-1006.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Relation of hemoglobin measured at different times in pregnancy to preterm birth and low birth weight in Shanghai, China
AU - Zhou, Li Ming
AU - Yang, Wen Wei
AU - Hua, Jia Zeng
AU - Deng, Chun Qin
AU - Tao, Xu Guang
AU - Stoltzfus, Rebecca J.
PY - 1998/11/15
Y1 - 1998/11/15
N2 - This paper addresses two questions: 1) What is the relation of hemoglobin in the second gestational month to preterm birth and low birth weight? 2) How does the relation differ when hemoglobin in the fifth or eighth month or the lowest pregnancy hemoglobin are examined in place of first trimester values? These relations were examined prospectively in 829 women from Shanghai, China in 1991-1992. The population was nearly homogeneous by race, parity, antenatal care, and smoking. Rates of birth Outcomes were con, pared between hemoglobin categories based on 10 g/liter groupings, with 110-119 g/liter as the reference group. Rates of low birth weight and preterm birth (but not small-for-gestational age) were related to early pregnancy hemoglobin concentration in a U-shaped manner. The relative risks (95% confidence intervals) for preterm birth in women by g/liter of hemoglobin were 2.52 (0.95-6.64) for ≥130 g/liter, 1.11 (0.41-2.99) for 120- 129 g/liter, 1.64 (0.77-3.47) for 100-109 g/liter, 2.63 (1.17-5.90) for 90- 99 g/liter, and 3.73 (1.36-10.23) for 60-89 g/liter. Use of hemoglobin values in the fifth or eighth month attenuated the association with preterm birth. When lowest pregnancy hemoglobin values were used, the association of anemia with both outcomes was obscured, and risk of preterm birth at high hemoglobin values increased dramatically.
AB - This paper addresses two questions: 1) What is the relation of hemoglobin in the second gestational month to preterm birth and low birth weight? 2) How does the relation differ when hemoglobin in the fifth or eighth month or the lowest pregnancy hemoglobin are examined in place of first trimester values? These relations were examined prospectively in 829 women from Shanghai, China in 1991-1992. The population was nearly homogeneous by race, parity, antenatal care, and smoking. Rates of birth Outcomes were con, pared between hemoglobin categories based on 10 g/liter groupings, with 110-119 g/liter as the reference group. Rates of low birth weight and preterm birth (but not small-for-gestational age) were related to early pregnancy hemoglobin concentration in a U-shaped manner. The relative risks (95% confidence intervals) for preterm birth in women by g/liter of hemoglobin were 2.52 (0.95-6.64) for ≥130 g/liter, 1.11 (0.41-2.99) for 120- 129 g/liter, 1.64 (0.77-3.47) for 100-109 g/liter, 2.63 (1.17-5.90) for 90- 99 g/liter, and 3.73 (1.36-10.23) for 60-89 g/liter. Use of hemoglobin values in the fifth or eighth month attenuated the association with preterm birth. When lowest pregnancy hemoglobin values were used, the association of anemia with both outcomes was obscured, and risk of preterm birth at high hemoglobin values increased dramatically.
KW - Anemia
KW - Hemoglobins
KW - Infant, low birth weight
KW - Infant, premature
KW - Infant, small for gestational age
KW - Pregnancy
UR - http://www.scopus.com/inward/record.url?scp=0032533576&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0032533576&partnerID=8YFLogxK
M3 - Article
C2 - 9829872
AN - SCOPUS:0032533576
VL - 148
SP - 998
EP - 1006
JO - American Journal of Epidemiology
JF - American Journal of Epidemiology
SN - 0002-9262
IS - 10
ER -